The Phylogeny of Hornless Ruminants and a Description of the Cranium of Archaeomeryx

The Phylogeny of Hornless Ruminants and a Description of the Cranium of Archaeomeryx

Author: Sawney David Webb

Publisher:

Published: 1980

Total Pages: 54

ISBN-13:

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"We analyze the interrelationships of the several groups of hornless ruminants and show which of them lie nearest the higher ruminants. The phylogenetic progression within Ruminantia proceeds from Hypertragulidae through Tragulidae to Leptomerycidae to Gelocidae to Moschidae and thence to the horned ruminants. Archaeomeryx of the late Eocene is recognized as a primitive member of the Leptomerycidae; the living Tragulidae actually represent a more primitive ruminant stock. We introduce the name Moschina for the Gelocidae and the Moschidae and the term Eupecora for the higher ruminant groups bearing horns, antlers, and ossicones. We also propose Neoselenodontia, above the subordinal level, to include both the Ruminantia and their sister group, the Tylopoda. The stratigraphic records of the five lower ruminant families appear relatively complete with the exception of the Tragulidae, which are poorly known prior to the Miocene. The exclusively North American distribution of the family Hypertragulidae and many of the Tylopoda suggests that the Ruminantia may have originated in North America. The Tragulidae, exclusively Old World and predominantly subtropical, presumably originated by colonization and isolation in the Old World. Thereafter ruminant evolution centered in the Old World, but representatives of every major group reached North America"--P. 121.


The Rut

The Rut

Author: Ron Spomer

Publisher:

Published: 1996

Total Pages: 166

ISBN-13:

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Nature enthusiasts know rut is a three-letter word for sex and aggressive action. The fall phenomenon, occurring when North American horned and antlered animals are at their physical prime, features dramatic and dangerous fights, chasing, scent marking, and rubbing. It is the time of year when the thrilling whistle of a bull elk sweeps across the canyon; when lovesick bull moose curiously court dairy cows, and bighorn rams collide with one another with the combined force of 2400 foot-pounds. A hundred exciting color photographs vividly illustrate this spectacular fall ritual and author Ron Spomer's descriptive text explains the origins and reasons for this fascinating, seemingly bizarre behavior. For example, why do whitetail bucks tryst with one doe at a time while elk bulls wear themselves thin servicing a harem? Why, after the rut, do mule deer bucks cast their antlers and assume the identity of does? The Rut investigates and answers these questions and more about these compelling animal rituals, including rutting tactics as well as describing how terrain, habitat, climate and other factors combine to shape each species' specific strategy for perpetuating itself.